This is the error message: Oops, try again. It looks like rental_car_cost returns None instead of the correct amount (100) for 3 days.
I dont have a clue what is happening!!
I dont get it here is my code:
cost = days * 40
if days >= 7 and not days <= 3:
cost = cost - 50
elif days >= 3 and not days >= 7:
cost = cost - 20